package util;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Random;
import java.util.Set;

public class RandomNumber {  
	  
    /** 
     *  
     * @return Set<Integer> 
     */  
    public static Set<Integer> GetRandomNumber() {  
        Set<Integer> set = new HashSet<Integer>();  
        Random random = new Random();  
          
        while (set.size() < 4) {  
            set.add(random.nextInt(10));  
        }  
        return set;  
    }  
    
    public static String randomCode() {
    	 Set<Integer> set = GetRandomNumber();  
         Iterator<Integer> iterator = set.iterator();  
         String temp = "";  
         while (iterator.hasNext()) {  
             temp += iterator.next();  
         }  
         return temp;
        
    }
  
    
    public static void main(String[] args) { 
    		 System.out.println(new SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ssZ").format(new Date()));  
    }  
}  
